Oil refining process



Patented Aug. 29, 1939 v UNITED STATES OIL REFINING PROCESS HeliodorRustin and Karl Schuster, Berlin,

Germany No Drawing. Application August 23,

1938, Serial No. 226,385. In Germany September 3, 1936 9 Claims.

This invention relates to a process for the improvement or refining ofoils and is particularly intended for the improvement of naphtha oils,or oils from coal, brown coal and shale. The improved treatment of theoils has particular reference to the gum, potential gum, sulfur,coloring matter and odorous contents thereof.

Nearly all oils contain organically combined sulfur which is convertedinto sulfuretted hydrogen during treatment. Thus, earlier processes wereunable to work satisfactorily, because the materials used, for examplecopper, iron, and iron ore, soon became saturated with sulfur and losttheir activity.

The principal object of the present invention is to avoid thedisadvantages aforesaid and to provide a. continuous process which canwork without interruption and without deterioration of the catalyser.

The invention consists in conducting oil vapours together with reducinggases, such as hydrogen or carbon monoxide, over the oolitic oreminette, in the presence of steam. The ore should preferably be treatedwith reducing gases at an elevated temperature before the oil vapoursare admitted.

The presence of steam and reducing gases during the treatment keeps thecatalytic material permanently clean and active so as to make theprocess an absolutely continuous one.

Extensive investigation has shown that the oolitic ore makes aparticularly fine catalyser. It is necessary, however, to keep it freefrom deposits and sulfur which it may take up and to do this bycontinuous removal. This is effected by the addition of steam to thereducing gases accompanying the oil vapours.

The proportion of steam in the reducing gases must be adjusted so that acertain equilibrium is maintained in the state of the minette, for thelatter must be neither entirely oxidized nor entirely reduced. It hasbeen found that the amount of steam is best determined by saturating thegases accompanying the oil with moisture at 65 C. to 95 C. The amount ofthe said gases is preferably 80 to 200 litres per 1 kilogramme of oil,but this largely depends upon the quantity of organically combinedsulfur in the oil under treatment.

The working temperature of the process should be about 300 C. to 450 C.At lower temperatures, decomposition of steam and removal of sulfur fromthe minette might not be sufiiciently energetic.

When oils are treated according to the process above described anddistilled, it is found that they have lost every kind of objectionablesmell and are water white, their sulfur, gum and potential gum being sofar reduced as to be well within permissible limits.

The invention is not merely a laboratory procedure. It has been carriedout on a large technical scale which has proved that the process canwork for considerable periods without deterioration of the catalyser.Hy- 10 drocarbons and organically combined sulfur do not affect theworking since the sulfur is continuously removed. However, oils oftencontain mechanical impurities and fractions which do not fully evaporateat a given temper- 5 ature, and sometimes even tarry matter. In suchcases, it is obvious that the catalyser must get coated or clogged sothat its full activity will be lost. Also, there may be a slightdecomposition of certain bodies with deposition of carbon 20 having thesame effect. In this event, the catalyser must be freed from allimpurities after a period of working and this can be effected only byoxidation.

To carry out this oxidation in the reaction 25 chamber or tower is notpractical because the temperatures rise so high as to smelt the minetteor bake it, which naturally renders it unfit for further use. Toregenerate the ore by removing it entirely from the tower and burning itout- 30 side involves interruption of the process and a serious loss oftime, when the many days required for cooling the whole mass and heatingup the new charge are taken into consideration.

This difficulty is successfully overcome by re- 35 moving the catalyserfrom one end of the reaction chamber in small quantities and replacingthe quantity removed by feeding in at the other end a correspondingcharge of new or regenerated ore. This is readily accomplished withoutinterruption '40 of the working by an arrangement of valve devices orshutters at the top and bottom of the tower. Such an arrangement can beconstructed in many different ways and the particular constructionadopted is of no consequence so far as 45 the invention is concerned.The important feature in this regard is the principle of piecemealrenewal of the catalytic mass without interruption of the working.

The charge of fresh ore must be kept in a 50 container wherein it can bepreheated before entering the reaction chamber, otherwise condensationof oil and watery vapours would take place inside the reaction chamberdue to the introduction of the cold ore. Furthermore, the

fresh charge must be in a reduced state and not oxidized whenintroduced, otherwise part of the oil vapours would be oxidised uponcoming into contact with the oxide. For these reasons, the hopper orstorage vessel must be provided with suitable heating means and sodevised or adapted that steam or reducing gases can circulate throughthe ore for the purpose of heating and reducing the same.

In effect, the invention as above described provides an absolutelycontinuous process with the contact mass showing always an equal purityand composition. Consequently, the finished product also has at alltimes an equally high quality.

A further important object of the invention is a process which enablesall other additional treatments of the product, apart from. the usualdistillation, to be eliminated. For example, there is elimination of thewashing with acid or sodium hydroxide which causes considerable loss ofsubstance. The invention therefore further provides for the removal ofany noxious substance contained in the oil after the treatmenthereinbefore described. As already stated, the organically combinedsulfur of the oils leaves the reaction chamber in the form ofsulfuretted hydrogen which may be partly retained in the condensate. Theoil also may retain some moisture from the steam. present during theprocess. Neither of these bodies must be allowed to remain in the oilproduct. The employment of sodium hydroxide for the removal of Water andsulfuretted hydrogen is rather expensive. Consequently, the inventionprovides for conducting the condensate from the reaction chamber firstthrough a medium which absorbs moisture from oil, for example lime orcommon salt, and secondly through a medium which absorbs sulfurettedhydrogen. For the second medium, it is very advantageous to use the veryfine part of the minette which has been crushed for use in the reactionchamber and which is to fine for that purpose. This fine material, whichotherwise would have to be wasted, forms an ideal filtering medium sofar as sulfuretted hydrogen is concerned. Any suitable sieving orseparating means may be employed for grading the minette so that anappropriate grade is used in the tower, the fines being available forfiltering, as indicated.

Salt used for removal of moisture from the condensate can easily berecovered by evaporation of the absorbed water.

We claim:

1. Continuous process for treating oils consisting in conducting oilvapours with reducing gases over the oolitic ore minette in the presenceof steam and at a temperature of 300 C. to 450 C., the proportion ofreducing gases and steam being so adjusted that released sulfur escapesfrom the reaction chamber in the form of sulfuretted hydrogen and doesnot form permanent sulfide of iron in the chamber.

2. Continuous process for treating oils comprising conducting oilvapours with reducin gases over the oolitic ore minette in the presenceof steam and at a temperature of 300 C. to 450 C.

3. Continuous process for treating oils comprising conduc-ting oilvapours with reducing gases over the oolitic ore minette at atemperature of 300 C. to 450 C., the reducing gases being saturated withwater vapour at a temperature of C. to C.

4. Continuous process for treating oils comprising conducting oilvapours with reducing gases over the oolitic ore minette at a temperature of 300 C. to 450 C. and in the presence of an adjusted quantity ofsteam, and gradually removing the charge of ore and replacing it withfresh ore.

5. Continuous process for treating oils comprising conducting oilvapours with reducing gases over the oolitic ore minette at atemperature of 300 C. to 450 C. and in the presence of an adjustedquantity of steam, removing portions of the charge of ore during theworking and replacing such portions by preheated portions in a reducedcondition.

6. Continuous process for treating oils comprising conducting oilvapours with reducing gases over the oolitic ore minette at atemperature of 300 C. to 450 C. and in the presence of an adjustedquantity of steam, removing portions of the ore during the working andreplacing such portions by pre-heated portions from, which a removal ofoxygen has been effected.

'7. Continuous process for treating oils comprising conducting oilvapours with reducing gases over the oolitic ore minette at atemperature of 300 C. to 450 C. and in the presence of an adjustedquantity of steam, and conducting the oil condensate from the reactionthrough a water absorbent and through a sulfur remover.

8. Continuous process for treating oils comprising conducting oilvapours with reducing gases over the oolitic ore minette at atemperature of 300 C. to 450 C. and in the presence of an adjustedquantity of steam, and conducting the oil condensate from the reactionthrough a water absorbent andthrough a filtering medium containing ironoxide.

9. Continuous process for treating oils comprising conducting oilvapours with reducing gases over crushed and graded oolitic ore minetteat a temperature of 300 C. to 450 C. and in the presence of an adjustedquantity of steam,

and conducting the oil condensate from. the reaction through a waterabsorbent and through the fines resulting from the crushing and gradingof the oolitic ore.

HELIODOR ROSTIN. KARL SCHUSTER.

